C1orf21

C1orf198 is a protein-encoding gene found on the reverse strand of chromosome 1 at the locus 1q25.3.[9]

C1orf21 is located on the long arm of chromosome 1. It is found at position 5q23.1.

Cytogenic band: 1q25.3

Chromosome one is one of the longest chromosomes, in which C1orf21 spans from 184,385,826 to 184,390,390 bases, resulting with mRNA transcript that is 10,278 nucleotides long with 4 exons. The protein is 121 amino acids long, containing a domain of unknown function known as DUF4612.

NCBI gene and RNA-Seq revealed that C1orf21 is expressed in all tissues at a low to moderate level, however, it is mostly expressed in the skin, brain and prostate.

There was over 7 promoters that were predicted, but the true promoter was 1111 base pairs long known as .[10]

Many transcription factor (TF) binding sites have been predicted through Genomatix. Some important binding cites include MYRE, MARs, and Bright.

MYRE is a myelin regulatory factor. Myelin is produced in the central nervous system and plays a large role in axons. MARs is a special AT-rich sequence-binding protein 1, predominantly expressed in thymocytes, binds to matrix attachment regions. Bright helps with B cell regulator of IgH transcription.

It was predicted that the location of C1orf21 is in the nucleus with 62.2% certainty. The mitochondria was predicted at 17.4%: mitochondrial, while the cytoskeleton, and vascular system at 4.3%.[11]

C1orf21 protein is 121 amino acids long with a molecular weight of 18,7 kDa with an isoelectric point of 5.08. It is believed that the protein interacts with the nuclear membrane and contains an unknown domain known as DUF4612. For the secondary and tertiary structure it is predicted that there are many alpha helices in the structure, with the rest of the protein having a disordered structure.[12]

PHYRE. An α-helix from 18 amino acids of C1orf21.

I-TASSER software generated a prediction of the tertiary structure of C1orf21.

Figure 3.  Unrooted phylogenetic tree of C1orf21 orthologs. Adi [Acropora digitifera, Stony coral pulp], Ate [Anabas testudineus], Bbe [Branchiostoma belcheri, crown-of-thorns starfish],  Cat [Cercocebus atys], Cmi [Callorhinchus milli], Ena [Echeneis naucrates], Fgl [Fulmarus glacialis], Gga [Gallus gallus, chicken], Ggg [Gorilla gorilla gorilla], Hbu [Haplochromis burtoni], Hle [Haliaeetus leucocephalus], Hsa [Homo sapiens, human], Mul [Macaca mulatta], Nfu [Nothobranchius furzeri], Oha [Ophiophagus hannah], Ptr [Pan troglodytes], Pvi [Pogona vitticeps, central bearded dragon], Rty [Rhincodon typus], Xla [Xenopus laevis, African clawed frog] Uma [Ursus maritimus]. Tree made with a neighbor-Joining method using a ClustalW-formatted set of sequences as input1.1 Clustal W [16]

There are no isoforms or paralogs of C1orf21 that are known.

C1orf21 is found in most classes of vertebrates and some invertebrates. The most distant ortholog of C1orf21 is Acropora digitifera, which diverged an estimated 824 million years ago.[17] There is no traces of the C1orf21 gene in organisms that are traced beyond invertebrates, such as fungi, plants, protists, or single celled organisms.[18]

The domain of unknown function 4612 (DUF4612) was highly conserved in most orthologs.